Arent they awesome?!
Characteristics of Sponges!
Some of the characteristics of sponges include an in-definate symmetry. It can vary from sponge to sponge. They also tend to be multicellular and contain few tissues and absolutely no organs and no nervous system. When they reach adulthood, they become either benthic or sessile, attaching to the ground or various other objects.
Man Eating Barrel Sponge!
As you can see, sponges are at the top of the food chain...